So if you're doing US national security, you cannot accept the Obama position; any technology to which our "good guy" law enforcement could get access is guaranteed to also be a technology to which a "bad guy" foreign enemy combatant could similarly gain access.
If you're a major US corporation, you cannot accept the Obama position; any technology to which our "good guy" law enforcement could get access is guaranteed to also be a technology to which a "bad guy" foreign intelligence/espionage agent could similarly gain access.
So as far as that is concerned, it is binary. You can either be secure against foreign threats, in which case you are also as a side effect impenetrable to the local "good guys". Or you can be penetrable by the local "good guys" and also as a side effect penetrable by the foreign "bad guys".
The argument advanced against Obama's position is that A) it fundamentally fails to acknowledge this reality, and B) seems to argue for deliberately compromising national security in order to... preserve national security? In other words, it is not only unrealistic, it is in fact nonsensical and self-contradictory.